Early fulminant liver allograft failure is a post-transplant syndrome presenting as massive haemorrhagic necrosis of the graft. A single organ Shwartzman reaction has previously been suggested as a cause. We report on a patient who lost her liver graft due to fulminant graft failure ten days after orthotopic liver transplantation (OLT), the liver showing massive haemorrhagic necrosis. Fresh thrombosis was noted in the portal and hepatic veins. As a Shwartzman reaction could be expected to lead to complement deposition in vessel walls, tissue was analyzed for the presence of complement components. However, even though protein-rich and fibrinogen-containing deposits were detected within the vessel walls, these deposits were not immunoreactive for complement (C3 and Clq). These findings suggest that pathogenesis of fulminant liver allograft failure differs from that of a complement-mediated Shwartzman reaction, or of a hyperacute rejection, where IgM and Clq had previously been detected in hepatic veins and arteries.